Documentation of mesh import in 2D

Usage

The files for the mesh are expected to have the following specified relation to the input file <FILE> e.g. for the input file example.cig it is searched for:

example_Coord.dat	File with coordinates of the mesh vertices.
example_Elms.dat	File with information of the mesh cells.
example_Attr.dat	File with cell, edge and vertex attributes.
example_EdgRadia.dat	File with radia of circular edges.
example_EdgCorr.dat	File with information about periodic edges.

Furthermore, semi-infinite rectangles can be defined via the file for the input parameter.

Type	Name (default value)	Stands for		Compulsory
string array	InfiniteQuad (empty)	Array of semi-infinite rectangles, e.g. string array InfiniteQuad { 1 "2 1 4", 2 "104 103 4" }		No

Coordinate file

Format: node x y

For instance:

1 1.0 1.0
2 0.0 0.5
3 0.0 0.0
4 -1.0 2.0

It is recommended to use the first column as node number which may start with 1 (by default) or 0. However, furtherone only the assumed node number which is the line number (or line number -1 for start value 0).

Elements file

File with node numbers of triangles or quads.

Format: triangle node0 node1 node2

or

Format: quad node0 node1 node2 node3

For instance:

1 1 2 3

or

1 1 2 3 4

Attribute file

File with attributes of nodes, edges or cells.

Format for a node attribute: nr node0 attr

Format for a edge attribute: nr node0 node1 attr

Format for a triangle attribute: nr node0 node1 node2 attr

Format for a quadrilateral attribute: nr node0 node1 node2 node3 attr

The first column is only used to be in the same format as the other files. The attribute is some integer value which can be used for mesh refinement strategies, boundary conditions or for cell-wise defined material functions.

Edge radia file

File with radia of circular edges.

Format: nr node0 node1 radius

Negative sign of the radius means that the arc is on the right side of the edge from node0 to node1 and positive sign that it is on the left side.

Edge correlation file

File to identify that two geometrical edges are topological identical, which creates periodic boundaries.

Format: nr node0 node1 node2 node3

The edge with the nodes node0 and node1 is identified with the edge with the nodes node3 and node2. Let for example the both edges be vertical. Proper edge correlation would be if node0 and node3 are bottom nodes and node1 and node2 are top nodes of the respective edge.